The present invention relates to a silver halide photographic light-sensitive material and in particular to a silver halide photographic light-sensitive material having a dyed hydrophilic colloid layer.
In silver halide photographic light-sensitive materials, it is often carried out for absorbing light of specific wavelength region to color photographic emulsion layer or other layers.
When it is necessary to control spectral composition of light which is to enter into photographic emulsion layer, a colored layer is provided at the position remoter from a support than the position of photographic emulsion layer.
Such colored layer is called a filter layer.
When a plurality of photographic emulsion layers are present as in multi-layer color light-sensitive materials, the filter layer may be positioned between these emulsion layers.
A colored layer is provided between photographic emulsion layer and support or on the side of support opposite to the side on which emulsion layer is present for the purpose of inhibiting blur of image, namely, halation which is caused by the phenomenon that light scattered at the time of passing through photographic emulsion layer or after transmitting therethrough is reflected at interface between emulsion layer and support or at the surface of light-sensitive material opposite to the surface on which the emulsion layer is present and again enters into the emulsion layer.
Such colored layer is called an antihalation layer. In case a plurality of photographic emulsion layers are present as in multi-layer color light-sensitive material, the antihalation layer may be provided between these layers.
Coloration of photographic emulsion layer is also carried out in order to inhibit reduction of sharpness of image caused by scattering of light in photographic light-sensitive layer (this phenomenon is generally called irradiation).
In many cases, these layers to be colored comprise hydrophilic colloid and so normally a water-soluble dye is contained in the layers for coloration thereof.
This dye must satisfy the following requirements.
(1) It has proper spectral absorption depending on use. PA1 (2) It has sufficiently high absorbance. PA1 (3) It is photographic-chemically inert. That is, it has no adverse effects in chemical sense on properties of silver halide photographic emulsion layer, for example, it does not cause reduction of sensitivity, fading of latent image and fogging. PA1 (4) It does not cause changes with time such as discoloration during preparation of coating solution (photographic emulsion) and preparation and storage of emulsion. PA1 (5) It does not result in difficulty in coating due to increase of viscosity when it is added to coating solution (photographic emulsion). PA1 (6) It is decolored or dissolved and removed in the course of photographic processing and does not leave harmful coloration on photographic light-sensitive material after processing.
For satisfying these requirements, many dyes which absorb visible light or ultraviolet ray have been proposed.
Especially, for photographic elements sensitized for wavelength of 700 nm or less, triarylmethane dyes and oxonol dyes have been widely used for improvement of images as mentioned above.
On the other hand, recently it has been desired to develop antihalation dyes and anti-irradiation dyes which absorb infrared region for photographic light-sensitive materials as recording materials sensitized in infrared region, for example, those which record output of near infrared laser.
For example, as one method for exposing such photographic light-sensitive materials, there is known an image forming method so-called scanner system which comprises scanning an original and exposing silver halide photographic light-sensitive material according to the image to form negative image or positive image corresponding to the image of original.
Semiconductor laser is most advantageously used as light source of the scanner system. This semiconductor laser has the advantages that it is small in size; inexpensive; easy in modulation; longer in life than other He--Ne laser, argon laser and the like; and besides, emits light in infrared region and hence, when light-sensitive materials having sensitivity to infrared region is used, bright safe light can be used and thus handling properties become superior.
As dyes for photographic light-sensitive materials having sensitivity in infrared region, indoaniline dyes, dyes formed from 2-carbamoyl-1-naphthol and color developing agents, polymethine dyes and the like have been known which are disclosed, for example, in Japanese Patent Kokai Nos. 50-100116, 55-21094-21096, 61-174540, 62-3250, and 62-123454. However, these known dyes are not sufficiently long in their absorption wavelength for absorbing semiconductor laser beam of, for example, 780 nm, are low in stability with time, are insufficient in decoloration in the course of photographic processing, must be used in a considerably large amount for sufficient development of effect because of their low absorbance, may cause desensitization or increase of fog because they are photographic-chemically not inert, and increase viscosity of coating solution to result in difficulty in coating and thus none of them satisfy all of the above requirements (1)-(6). Therefore, there have been desired to develop dyes for photographic light-sensitive materials which make the best use of the characteristics of semiconductor laser which possesses excellent properties mentioned above.